package main

import (
	"crypto/tls"
	"fmt"
	"log"
	"net/http"
	"os"
	"strconv"
	"strings"
	"unicode"

	"git.fromouter.space/hamcha/tg"
	"github.com/spf13/viper"
)

type config struct {
	Token                 string
	Bind                  string
	WebhookURL            string
	WebhookPath           string
	MaxRequestsPerMessage int
	Log                   bool
}

func checkErr(err error, msg string, args ...interface{}) {
	if err != nil {
		fmt.Printf("FATAL ERROR\n"+msg+":\n  ", args...)
		fmt.Println(err.Error())
		os.Exit(1)
	}
}

var api *tg.Telegram
var cfg config

func main() {
	viper.AutomaticEnv()

	bind := viper.GetString("bind")
	if bind == "" {
		panic("Missing BIND")
	}

	token := viper.GetString("token")
	if token == "" {
		panic("Missing TOKEN")
	}

	webhookURL := viper.GetString("webhookurl")
	if webhookURL == "" {
		panic("Missing WEBHOOKURL")
	}

	webhookPath := viper.GetString("webhookpath")
	if webhookURL == "" {
		panic("Missing WEBHOOKPATH")
	}

	// Set default maxreq
	if cfg.MaxRequestsPerMessage < 1 {
		cfg.MaxRequestsPerMessage = 5
	}

	// Ignore CA errors
	http.DefaultTransport.(*http.Transport).TLSClientConfig = &tls.Config{InsecureSkipVerify: true}

	api = tg.MakeAPIClient(token)
	api.SetWebhook(webhookURL)
	api.HandleWebhook(bind, webhookPath, webhook)
}

type CardFaceFlipPics struct {
	Normal   string
	Flipped  string
	Ponyhead string
	MCM      string
}

func webhook(update tg.APIUpdate) {
	// Handle inline queries (99% of the usage I hope)
	if update.Inline != nil && update.Inline.Query != "" {
		query := update.Inline.Query
		results, err := mlpapiSearch(query)
		if err != nil {
			fmt.Println(err)
			// DO SOMETHING
			return
		}
		if cfg.Log {
			log.Printf(" -> %d cards", len(results.Data))
		}

		photos := make([]tg.APIInlineQueryResultPhoto, len(results.Data))
		for i, card := range results.Data {
			face, caption, buttons := getCardEntry(card, 0)
			photos[i] = tg.APIInlineQueryResultPhoto{
				Type:     "photo",
				ResultID: strconv.FormatInt(card.GUID, 10),
				PhotoURL: face,
				ThumbURL: face,
				Title:    card.FullName,
				Caption:  caption,
				Width:    344,
				Height:   480,
				ReplyMarkup: &tg.APIInlineKeyboardMarkup{
					InlineKeyboard: [][]tg.APIInlineKeyboardButton{buttons},
				},
			}
			// Flip width/height for problems
			if card.Type == "Problem" {
				photos[i].Width, photos[i].Height = photos[i].Height, photos[i].Width
			}
		}

		err = api.AnswerInlineQuery(tg.InlineQueryResponse{
			QueryID: update.Inline.QueryID,
			Results: photos,
		})
		if err != nil {
			fmt.Println(err)
			// DO SOMETHING
			return
		}
	}

	// Check for card requests
	if update.Message != nil && update.Message.Text != nil {
		requests := getCardRequests(*update.Message.Text)
		if len(requests) > cfg.MaxRequestsPerMessage {
			api.SendTextMessage(tg.ClientTextMessageData{
				ChatID:  update.Message.Chat.ChatID,
				Text:    fmt.Sprintf("You asked for way too many cards (%d!), please only ask me for at most %d cards in a single message.", len(requests), cfg.MaxRequestsPerMessage),
				ReplyID: &update.Message.MessageID,
			})
			return
		}
		cardmedia := []tg.APIInputMediaPhoto{}
		errlist := []string{}
		for _, cardname := range requests {
			cards, err := mlpapiSearch(cardname)
			if err != nil {
				errlist = append(errlist, cardname)
			} else {
				if cfg.Log {
					log.Printf(" -> %d cards", len(cards.Data))
				}
				for _, card := range cards.Data {
					face, _, _ := getCardEntry(card, 0)
					cardmedia = append(cardmedia, tg.APIInputMediaPhoto{
						Type:  "photo",
						Media: face,
					})
					if card.Type == "Mane" {
						face, _, _ := getCardEntry(card, 1)
						cardmedia = append(cardmedia, tg.APIInputMediaPhoto{
							Type:  "photo",
							Media: face,
						})
					}
				}
			}
		}
		if len(cardmedia) > 0 {
			api.SendAlbum(tg.ClientAlbumData{
				ChatID:  update.Message.Chat.ChatID,
				Media:   cardmedia,
				Silent:  true,
				ReplyID: &update.Message.MessageID,
			})
		}
		if len(errlist) > 0 {
			api.SendTextMessage(tg.ClientTextMessageData{
				ChatID:  update.Message.Chat.ChatID,
				Text:    "I couldn't find these cards you mentioned: " + strings.Join(errlist, ", "),
				ReplyID: &update.Message.MessageID,
			})
		}
	}

	// Handle inline callback requests (flipped cards)
	if update.Callback != nil {
		if update.Callback.Data != nil && strings.HasPrefix(*update.Callback.Data, "FLIP") {
			parts := strings.SplitN(*update.Callback.Data, ",", 3)
			card, err := mlpapiGetCardByID(parts[1])
			facenum, _ := strconv.Atoi(parts[2])
			if err == nil {
				face, caption, buttons := getCardEntry(card, facenum)
				api.EditMedia(tg.ClientEditMediaData{
					InlineID: *update.Callback.InlineID,
					Media: tg.APIInputMediaPhoto{
						Type:  "photo",
						Media: face,
					},
				})
				api.EditCaption(tg.ClientEditCaptionData{
					InlineID: *update.Callback.InlineID,
					Caption:  caption,
					ReplyMarkup: &tg.APIInlineKeyboardMarkup{
						InlineKeyboard: [][]tg.APIInlineKeyboardButton{buttons},
					},
				})
			}
		} else {
			fmt.Println("Unknown callback: ", *update.Callback.Data)
		}
		api.AnswerCallback(tg.ClientCallbackQueryData{
			QueryID: update.Callback.ID,
		})
	}
}

func getCardRequests(str string) (out []string) {
	remaining := str
	for len(remaining) > 1 {
		nextToken := strings.Index(remaining, "[[")
		if nextToken < 0 {
			break
		}
		endToken := strings.Index(remaining[nextToken:], "]]")
		if endToken < 0 {
			break
		}
		out = append(out, remaining[nextToken+2:nextToken+endToken])
		remaining = remaining[nextToken+2+endToken:]
	}
	return
}

func getCardEntry(card CardData, flipped int) (string, string, []tg.APIInlineKeyboardButton) {
	cid := toCardID(card.AllIDs[0])
	buttons := []tg.APIInlineKeyboardButton{
		{
			Text: "Ponyhead",
			URL:  "https://ponyhead.com/cards/" + cid,
		},
	}

	captions := []string{}
	suffix := ""
	if card.Type == "Mane" {
		suffix = ""
		num := 1
		if flipped != 0 {
			suffix = "b"
			num = 0
		}

		buttons = append(buttons, tg.APIInlineKeyboardButton{
			Text:         "🔄",
			CallbackData: fmt.Sprintf("FLIP,%d,%d", card.GUID, num),
		})
	}
	face := fmt.Sprintf("http://ponyhead.com/img/cards/%s%s.jpg", cid, suffix)
	return face, strings.Join(captions, " - "), buttons
}

func toCardID(id string) string {
	id = strings.ToLower(id)
	idx := strings.IndexFunc(id, unicode.IsLetter)
	num, set := id[:idx], id[idx:]
	return set + num
}